A car campaign being driven by a leading DUP politician has moved up a gear, the Belfast Telegraph can reveal.

Gregory Campbell has called for an end to the discrepancy between the miles a gallon claims that car manufacturers make about their vehicles and the actual miles per gallon that those cars will achieve.

The East Londonderry MP has tabled a House of Commons motion calling for the motor industry to implement a more realistic driving assessment.

"Constituents have raised with me the discrepancies that exist between claims of car manufacturers and the actual miles per gallon that cars can achieve in the real world," he said.

"Nearly 2.5 million new cars were bought last year in the UK and in brochures for the vast majority there was a 20%-plus differential in the miles per gallon claimed and what could be achieved. This means, for example, if a manufacturer claims that a new vehicle was capable of 50 miles per gallon the actual performance was more likely to be under 40 miles per gallon.

"For an average mileage of 10,000 to 12,000 miles driven annually this is a massive disparity between what the manufacturer is claiming it would cost to drive those miles and what it actually does cost in the real world."

Mr Campbell said the current MPG test used in the UK - the New European Driving Cycle - had been widely criticised for its unrealistic laboratory conditions.

"While this was meant to end in 2017 with a new 'Real Driving Emission' test, there is a concern that this date may be pushed back to 2020," he said.

"With the cost of fuel a top worry for people across the UK, even more so in Northern Ireland, it is imperative that people have accurate information to hand when they are making car purchases."

The largest consumer organisation in the UK, Which? magazine, has told Mr Campbell it wants to assist in ensuring that this issue is resolved satisfactorily.